A matsayinka na mulkin, yana da wuyar nunawa lokacin da aka hadu da kwan ya, don haka farkon fara ciki yana farawa tun daga ranar da aka fara yin jima'i.
Amfani
Daga wannan lokaci farawa da samuwa da kuma kara maturation daga cikin kwan. Ta haɗuwa tana faruwa a cikin guda zuwa makonni biyu.
Kafin jima'i namiji da mace ya haɗu da juna, zai ɗauki 3-6 hours. Tsarin spermatozoa, masu motsi zuwa ga kwai, sun haɗu da hanyoyi masu yawa, sakamakon haka, kawai mawuyacin kwayar halitta sun kai ga makasudin. Amma ɗaya daga cikinsu zai shiga cikin hadisin.
Lokacin da spermatozoon ya sami nasara a kan kwantar da kwai, to, nan da nan sai jikin ta fara sake gina aikinsa, wadda za a yi amfani da shi a yanzu don kiyaye ciki.
Yayin da haɗuwa, wani sabon kwayar halitta tare da lambartaccen kwayoyin halittarsa, wadda za ta ƙayyade jima'i na yaro, siffar kunnuwa, launi da idanu da sauran siffofi, an samo shi ne daga jikin mahaifa biyu, kowannensu yana da rabin saitin chromosomes kowace.
A ranar 4th - 5th, yaro ya hadu da mahaifa. A wannan lokaci, an riga ya tasowa a cikin tayin da ya kunshi kusan 100 kwayoyin.
Zubar da ciki cikin bango na mahaifa ya faru a farkon makon na uku. Bayan an kammala wannan zane. Hanya zuwa cikin mahaifa da kuma abin da aka makala a bangon shi shine haɗari mafi haɗari na tayi a cikin wata na fari.
Formation na tayin
A watan farko bayan ƙarshen tsarin shigarwa, farawar tayi zai fara. Hakan ya fara - ciwon gaba mai zuwa, amnion - ainihin nau'in tarin fuka da tayi. Gabatarwa da tayi a cikin watanni na farko na ciki yana farawa tare da samuwar litattafan jariri uku. Kowannensu yana wakiltar embryo na gabobin da aka rarraba da kyallen takarda.
- Kwayar embryon na waje ita ce ƙarancin tsarin mai juyayi, hakora, fata, kunnuwa, epithelium na idanu, hanci, kusoshi da gashi.
- Tsakanin tsire-tsire na tsakiya yana zama tushen asalin (tsokoki na skeletal, gabobin ciki, spine, guringuntsi, tasoshin, jini, lymph, jima'i jima'i).
- Tsarin embryon leaf na ciki yana zama tushen dashi na ƙwayar mucous membrane na jiki na numfashi, gabobin jikin gastrointestinal, hanta da kuma pancreas.
A ƙarshen watanni biyu na ciki, tayin (embryo) riga yana da tsawon 1 mm (ana iya gani da amfrayo). Akwai alamomin alamar wutsiya - canji na gaba. Akwai alamun shafi na zuciya da kuma bayyanar da jini na farko.